The present invention relates to an apparatus and to a method for visualization of an air stream by means of threads on aerodynamic surfaces in such a way that strips of adhesive tape populated with threads are produced automatically.
There are various possibilities of visualizing air streams on model surfaces in wind channels. One technique is the application of threads (8) onto the surface to be examined. The behavior of the threads provides a quick overview over the air stream conditions in the examined region. By illumination with UV-light, white colored threads or fluorescent synthetic materials are visible very well, so that these measurements can be documented by means of a video camera. The threads are adhered to the model surface, either one by one by means of spots of adhesive material or by means of pieces of adhesive tape, or they are adhered to one side of adhesive tapes (24) before the adhesive tapes are attached to the model in the form of continuous strips. In the high velocity domain, the technique used is the one with individually affixed threads, since strips of adhesive tape (24) should not disturb the surface of the model. In the wind channel—LSWT Bremen of Airbus Deutschland GmbH measurements are performed in the low velocity domain. Therefore, preconfigured strips of adhesive tape (24) with threads may be used.
The following documents relate to the field of visualization methods for wind channel experiments. A method for performing such methods is not described. However, the cited documents point out the importance of visualization of streams with the help of threads on aerodynamic surfaces.
J. P. Crowder Flow simulation techniques 4th International Symposium on flow visualization Paris August 1986
E. Thiel Anwendungsbeispiele herkömmlicher Sichtbarmachungsmethoden aus dem Strömungsversuch bei Dornier Interner Dornier Bericht (1970-1975 ?)
Agardograph 70/April 1962
J. P. Crowder Fluorescent Mini Tufts for flow visualization Boeing Commercial Airplanes Co. February 1977 Royal aircraft establishment Techn. Memo AERO 2038
D. G. Dobney et al. The “Minituft” surface flow visualization method April 1985
Strömungssichtbarmachung mit Minitufts im Niedergeschwindigkeitskanal der THD Studienarbeit H. Cremer TH Darmstadt February 1993
Eidg. Flugzeugwerke Emmen Bericht FO 1753 Sichtbarmachung der Strömung durch Minitufts für Windkanäle 1984